Electron impact excitation of higher energy states of molecular oxygen in the atmosphere of Europa L. Campbell, H. Tanaka, H. Kato, S. Jayaraman and M.J. Brunger Eur. Phys. J. D, 66 1 (2012) 26 Published online: 31 January 2012 DOI: 10.1140/epjd/e2011-20625-x